Performing An Emergency Shutdown; Restoring Power After An Emergency Shutdown - IBM DS4800 User, Installation And Maintenance Manual

v You are forced to shut down the storage subsystem without performing the
Attention:
the system after an unexpected shutdown.
Note: Unattended restoration of power is supported; however, if power restoration

Performing an emergency shutdown

Emergency situations might include fire, flood, extreme weather conditions, or other
hazardous circumstances. If a power outage or emergency situation occurs, always
turn off all power switches on all computing equipment. This will help safeguard
your equipment from potential damage due to electrical surges when power is
restored. If the storage subsystem loses power unexpectedly, it might be due to a
hardware failure in the power system or midplane (see Chapter 6, "Hardware
maintenance," on page 159).
Use this procedure to shut down the storage subsystem during an emergency:
1. If you have time, stop all I/O activity to the storage subsystem by shutting down
2. Check the LEDs (front and back). Make note of any Needs Attention LEDs that
3. Turn off all power-supply switches; then unplug the power cords from the

Restoring power after an emergency shutdown

Use the following procedure to restore power to the storage subsystem in a
configuration after an unplanned shutdown.
Risk of severe electrical shock – Never turn on the power to any equipment if
there is evidence of fire, water, or structural damage. Doing so might cause severe
electrical shock.
normal shutdown procedures (listed in "Turning off the storage subsystem" on
page 100) because of an emergency situation.
To avoid damage to the hardware, take special care when you restart
is attended, you should follow the best practices guidelines and the power
restoration sequence in "Turning on the storage subsystem" on page 97.
the host or disconnecting the storage subsystem logical drives through the host.
are on so you can correct the problem when you turn on the power again.
storage subsystem.
1. Visually check the equipment for damage. Is there evidence of damage to any
of the storage subsystem components, cables, or equipment attached to the
storage subsystem?
v Yes – Do not continue with this procedure. Contact your IBM service
representative for assistance. Depending on the current service agreements,
you might need to return the equipment to the factory or local service center
for repair.
v No – Go to step 2.
Potential data loss – Before resetting circuit breakers in the cabinet, ensure
that the storage subsystem and storage expansion enclosures power switches
are turned off. Resetting circuit breakers after an emergency situation while the
storage subsystem and storage expansion enclosure power switches are
turned on can cause potential data loss because the configuration components
might not be powered on in the correct sequence. See "Turning on the storage
subsystem" on page 97 for details about the correct power-on sequence.
2. Do whatever is necessary to cool the unit (replace the fans, use external fans
to cool the room, and so on).
Chapter 4. Operating the storage subsystem
103